1. Technical Field
The present invention relates generally to an improved dialing method on a mobile communications device and in particular to an apparatus and a method for handling accidental dialing. Still more particularly, the present invention provides an apparatus and a method for sending an alarm to the caller if accidental dialing is suspected and terminating the call if no response is received.
2. Description of the Related Art
Modern mobile communications devices have one key dialing or redialing features that make placing calls very convenient. However, this convenience has the danger of accidentally placing calls by pressing a key unintentionally, such as when the phone is being carried on a belt or in a purse. If the person at the other end picks up this call, he is powerless to alert the user about the error since the user is not listening to the phone. The result is that the user is charged for a lengthy call that was never intended.
One solution is to have a xe2x80x9ckey guardxe2x80x9d. This means the user must dial a sequence of numbers before the phone is activated. Typically this feature must be manually enabled and, if this is not done, then there is no protection. Even if there is automatic activation of the key guard after the last call is completed, there can be problems. If the time between the end of a call and reactivation of the keyguard is too short, then the user is required to go through the key guard again before initiating another phone call. If the time between the end of a call and reactivation of the keyguard is too long, accidental dialing may occur.
Another solution is a flip-up pad that physically covers the keypad of the cellular telephone. With such flip-up pads the keypad of the cellular telephone is only accessible when the flip-up pad is flipped to a position where it no longer covers the keypad. Furthermore, with some flip-up pads, the cellular telephone is only active when the flip-up pad has been opened for use. The use of a flip-up pad, while physically preventing accidental dialing when in a position covering the keypad, adds to the bulkiness of the telephone, requires additional manipulation from a user before a telephone call may be initiated, and may be inconvenient to some users of the cellular telephone.
Therefore, it would be advantageous to have an apparatus and a method to detect accidental phone calls and to take corrective actions to prevent excessive, unwanted phone charges.
An apparatus and a method is presented for detecting the accidental dialing of telephone numbers on a mobile communications device. Accidental dialing is typically caused by pressing a redial button or a speed dial button. The system works by monitoring the outgoing and incoming voice levels in order to detect an absence of conversation in both directions for a specified time period. An alarm system is activated if an absence of conversation is detected. This signifies that the phone connection is not being attended by anyone, i.e. it is an unattended communication due to perhaps an accidental dialing or due to the failure to adequately terminate a previously attended communication.
The alarm system sends a unique audio signal to the earpiece or other audio output device of the mobile communications device and waits for a response. The response might be pressing a particular key sequence or simply resuming the conversation. If a response is not detected after a short period of time, then the telephone call is automatically terminated. If a response is received, then, depending on user preferences, the monitoring system continues to function or can be disabled for the duration of the phone call.
In addition, the present invention provides a mechanism by which a called party may initiate a key sequence which generates a sequence of tones that are received by the phone that was accidentally dialed, to thereby output an audio alarm signal. If a response to the alarm signal is not received within a preset period of time, the telephone call is automatically terminated.
As a further embodiment of the present invention, a mechanism is provided by which emergency telephone numbers, which are stored in the memory of the telephone, do not activate the accidental dialing detection and handling features of the present invention. Thus, for example, if the telephone has emergency telephone numbers associated with a local police department, fire department, hospital, 911 and the like, these telephone numbers, when dialed, disable the accidental dialing detection and handling features of the present invention. By disabling the accidental dialing detection and handling features of the present invention in emergency situations, the possibility of automatically terminating the telephone call because the calling party is not able to converse is avoided.
As an even further embodiment of the present invention, a mechanism is provided for detecting tones associated with facsimile and computer modem transmissions. When these tones are detected by the present invention, the accidental dialing detection and handling features of the present invention are disabled in order to avoid erroneous termination of the facsimile and/or computer transmissions.